A Hawaii vacation for Charlize Theron and Sean Penn and has fueled speculation that the two have become Hollywood's newest power couple.

The actors were spotted together in Hawaii over the holidays, and spent time at Penn's Oahu beachfront home, according to USA Today. Photos of the two and another friend relaxing on the beach were posted by E! Online.com (http://www.eonline.com/news/495255/charlize-theron-and-sean-penn-spend-holidays-in-hawaii-head-back-to-l-a-together-see-the-pics)

"Charlize and Sean have been friends for years," a source told the magazine. "They have been spotted out together several times in the past few years. Even when Charlize was dating Stuart [Townsend]. They both had dinner with Sean several times."

Penn, 53, is a two-time Academy Award winner for his roles in "Mystic River" and "Milk." He has been married twice, to Madonna from 1985-89 and to Robin Wright from 1996-2010.

Theron, 38, won the Best Actress Academy Award for playing serial killer Aileen Wuornos in "Monster." She has been romantically linked with actors Craig Bierko and Stuart Townsend.